<?php

$rows = 5;
$colnums = 3;
echo "<htmnl><body>";
echo "<table border = 1>";
for ($i = 1; $i <= $rows; $i++) {
    echo "<tr>";
    for ($j = 1; $j <= $colnums; $j++) {
        if ((($i + $j) % 2) == 0) {
            $color = "#000000";
        } else {
            $color = "#ffffff";
        }
        echo "<td bgcolor = $color>$i,$j</td>";
    }echo "</tr>";
}echo "</table>";
echo "</body></html>";
?>
